Exhibition organizer and acting partner of the Design museum in Basel, Haldner was born in 1953 in the St. Galler Rheintal (Switzerland) and went to school in Gams and Sargans. Later he studied the history of art and literature at the University of Zürich with , where he completed coursework with Emil Maurer and Peter von Matt. He then worked as a scientific assistant at the Museum of Art in Winterthur and at the Graphic Collection of the ETH in Zürich. From 1984 to 1986 he organized exhibitions at the Gewerbemuseum in Basel, and from 1986 onward he’s directed and managed the museum. Since 1990 he’s directed the Design museum in Basel in cooperation with Matthias Götz. In this position he’s realised numerous national and international exhibitions. In 1998 he was a guest lecturer for visual communication at the University for Design in Karlsruhe.